Container with force differential flexible fastener



Feb. 4, 1969 s. AUSNIT 3,425,469

CONTAINER WITH FORCE DIFFERENTIAL FLEXIBLE FASTENER Filed April 6, 1966 I N VEN TOR. I

ang, m gfln; 0/ M ATTORNEYS United States Patent 3,425,469 CONTAINER WITH FORCE DIFFERENTIAL FLEXIBLE FASTENER Steven Ausnit, 124 E. 61st St., New York, NY. 10021 Filed Apr. 6, 1966, Ser. No. 540,713 US. Cl. 150-3 Int. Cl. B65d 51/00; A44!) 19/14 8 Claims ABSTRACT THE DISCLOSURE This invention relates to a flexible reclosable container having interlocking rib and groove elements for closing the interior of the container and having grip flanges for spreading the elements to gain access to the interior of the container, and in particular, this invention relates to a novel rib and groove element structure for providing a differential between the force required to open the container from the inside therof.

Recent developments in the manner of producing flexible containers have led to the use of a thinner, less costly film which has improved strength and uniformity of quality. Such a film may be extruded in the form of a cylindrical shell which is severed at proper intervals and heat sealed for forming a pouch having an opened end and having interlocking elements operably disposed at the inner surface adjacent the opening. The interlocking elements are generally disposed sufliciently below the opening of the container in order to allow grip flanges to extend above the elements which may be drawn apart to gain access to the interior of the container.

The reduced thickness of the film forming the walls of the container makes the reclosable type container competitive with less desirable packaging materials. However, the opening force required to spread the inerlocking elements may be appreciable if the elements are to be secured for resisting opening forces applied at the interior of the container due to the spreading force of the contents thereof. Furthermore, the opening force applied at the grip flanges tends to be concentrated in areas grasped by the user. Therefore, if a large interior force is to be resisted by the interlocking rib and groove elements, it would appear that a heavier type film would be required to sustain the opening force at the grip flanges.

In addition to the problem of reducing the cost of the film while sustaining opening forces at the grip flanges, it would appear to be highly desirable to the user to be able to open the reclosable container with appreciably less force than is required to be sustained at the interior of the container.

Accordingly, it is a principal object of this invention to provide a flexible container having interlocking rib and groove elements which are opened more easily from the outside than from the inside.

It is also an object of this invention to provide a flexible container having interlocking rib and groove elements wherein the groove element has a substantially heavier and more rigid hook arm disposed at the interior side of the rib element than the corresponding hook arm disposed at the outside of the container.

It is another object of this invention to provide interlocking rib and groove elements for a flexible container Patented Feb. 4, 1969 wherein the rib element has a head portion spaced from one of the side walls of the container and wherein the groove element has a hook arm disposed at the interior side of the rib element which occupies substantially more of the space between the head portion of the rib element and the attached side wall of the container than the corresponding hook arm occupies at the outside of the container.

It is a further object of this invention to provide a flexible container having interlocking rib and groove elements wherein the rib element has an overhanging engaging edge disposed to be closer to the attached side wall at the interior of the container than a corresponding edge is disposed relative to the side wall at the exterior of the container.

It is an additional object of this invention to provide a flexible container having interlocking rib and groove elements for closing and opening the container wherein the rib element has an overhanging engaging surface disposed at the interior of the container and forming an angle of less than with the profile axis of the attaching base portion of the rib element and wherein the overhanging engaging surface of the rib element at the exterior .of the container forms an angle with the profile axis of the base portion which is greater than 90.

These and other objects, features and advantages of the present invention will be understood in greater detail from the following description and the associated drawings wherein reference numerals are utilized in designating an illustrative embodiment and wherein:

FIGURE 1 is a sectional view of a flexible container having interolcking rib and groove elements which are more easily opened from the outside than from the inside, and which have the structural characteristics of this invention;

FIGURE 2 is a sectional view of an enlarged flexible container showing in greater detail the structure employed to develop a container which is more rigidly secured at the interior thereof than at the exterior;

FIGURE 3 is a sectional view similar to the view of FIGURE 2 showing an alternate form of the rib and groove element structure used to develop a differential between the opening force at the exterior of the container and the opening force at the interior thereof; and

FIGURE 4 is a further sectional view similar to the views of FIGURES 2 and 3 showing another form of the rib and groove element structure which may be utilized to develop an opening force at the exterior of the container which is appreciably less than the opening force required at the interior of the container.

The interlocking rib and groove elements of the flexible container according to this invention employs a rib or a groove member which is asymmetrical such that the configuration of the element facing interiorly of the container is more firmly interlocked than the configuration of the elements facing outwardly of the container. For instance, the inwardly facing portion of the groove element may be heavier and more rigid for resisting opening at the interior of the container, while the portion of the groove element facing exteriorly of the container may be more flexible and hence more easily separated from the rib element. Apart from the size of the interiorly facing and exteriorly facing portions of the groove element, the interlocking members may be structured such that a spreading force at the interior walls serves to increase the grip of the elements, while a spreading force at the exterior walls or grip flanges tends to separate the elements.

A flexible container of the type characterized in this invention has side walls 10 and 11 formed of a thin, plastic-like film which is folded to form a base portion 12 and which is heat sealed along the vertical sides of the container to form a pouch or enclosure 13. The side walls and 11 of the flexible container have rib and groove elements 14 and 15 respectively formed integrally with the film material as at points 16 and 1'7.

The film material forming the side walls It and 11 is allowed to extend above the interlocking elements 14 and 15 to provide flexible grip flanges 18 and 19. The flanges 18 and 19 may be held by the user and drawn apart for opening the interlocking rib and groove elements 14 and 15 respectively. The elements 14 and 15 may then be reclosed by applying pressure directly against the elements as is well understood.

Due to the thin character of the film forming the side walls 10 and 11 and hence the grip flanges 18 and 19, a spacer head 20 is formed longitudinally at the inner surface of the flange 19 to maintain separation of the flanges and to allow the user to readily distinguish one flange from the other. In particular, the edges 21 and 22 of the flanges 18 and 19 are made more readily discernible through the use of the spacer bead 20.

The nature of the rib and groove elements 14 and 15 R of the flexible container shown in FIGURE 1 are shown in more detail in the enlarged drawing of FIGURE 2. In FIGURE 2, the rib element 14 is shown to have a rounded head portion 23 and overhanging engaging edges 24 and '25 which extend outwardly and inwardly respectively of the flexible container. The rounded head portion 23 of the rib element 14 is secured to the inner surface 26 of the side wall 10 by a base portion 27. The base portion 27 maintains the overhanging engaging edges 24 and spaced from the inner surface 26 of the side wall 10 and attaches the entire rib element as at the point 28 to the side wall.

The groove element 15 ofthe flexible container shown in FIGURE 2 comprises first and second hook arms 29 and 30 which are formed integrally with the side wall 11 at the inner surface 31 thereof secured thereto at the point 32. The hook arm 29 has an extension portion 33 and a hook portion 34. The extension portion 33 extends about the rounded head portion 23 of the rib element 14, and the hook portion 34 engages the overhanging edge 24 of that element. Similarly, the hook arm 30 of the groove element 15 has an extension portion 35 which extends about the inner surface of the rounded head 23 and a hook portion 36 which engages the overhanging edge 25 of the rib element.

To develop the force differential between the opening requirements at the exterior of the container and at the interior of the container, the hook arm 30 is provided to be substantially heavier and substantially more rigid than the corresponding hook arm 29. In particular, the extension portion 35 has a thickness 37 which appreciably exceeds the thickness 38 of the corresponding extension portion 33. Also, the hook portion 36 has a thickness 39 which appreciably exceeds the thickness 40 of the corresponding hook portion 34. In addition, the hook portion 36 of the hook arm 30 occupies substantially more of the space between the engaging edge 25 and the inner surface 26 of the side wall 10 than the hook portion 34- occupies between the overhanging edge 24 and the inner surface 26 of the side wall 10. Accordingly, the hook arm 30 of the groove element 15 resists opening due to a spreading of the side walls 10 and 11 at the inside of the container, and the hook arm 33 opens relatively easily due to a spreading of the grip flanges 18 and 19. Hence, the objective of providing a force differential between the opening requirements at the interior and at the exterior of the container has been accomplished.

An alternate embodiment of the manner of achieving an opening force differential is shown in FIGURE 3 as comprising a rib element 41 and a groove element 42. The rib element 41 has overhanging engaging edges 43 and 44 which are displaced by different distances from the associated side wall 10 of the flexible container.

Similarly, the groove element 42 has hook arms 45 and 46 which are cooperable for engaging the rib element 41 at the engaging edges 43 and 44. In particular, the hook arm 45 has an extension portion 47 and a hook portion 48. The extension portion extends about the rounded head 49 of the rib element 41, and the hook portion 48 interlocks with the engaging edge 43. Similarly, the hook arm 46 has an extension portion 59 and a hook portion 51 for engaging the overhanging edge 44 of the rib element 41.

The force differential available from the embodiment of FIGURE 3 is dervied principally from the relative spacing of the overhanging edges 43 and 44 from the inner surface 26 of the side wall 10 and from the cooperable configuration of the hook arms 45 and 46 of the groove element. In particular, the smaller overhanging edge 44 will bend more readily and thereby separate from the shorter hook arm 51 more easily than the larger overhanging edge 43 will separate from its hook arm 48.

Further opening force differentials can be achieved in the structure of FIGURE 3 by enlarging the size and hence the rigidity of the hook arm 45 which is disposed at the interior side of the rib element 41. Also, the force differential can be increased or decreased by altering the spacing between the end face 52 of the hook arm 46 and the outer face 53 of the base portion 54 associated with the rib element 41. For instance, the spacing between the faces 52 and 53 is greater than the corresponding spacing associated with the hook arm 45. Hence, the flexible container will, to that degree, open more easily from the outside than from the inside.

A further embodiment of the force differential fastener of this invention is shown in FIGURE 4 and comprises a rib element 55 secured through a base 56 to the flexible wall 10. The rib element 55 has engaging edges 57 and 58 which are obliquely angled relative to the base 56. In particular, the overhanging edge 57 forms less than a angle with the profile axis 66 0f the base 56, and the overhanging edge 58 forms an angle greater than 90 with the profile axis 66.

The groove element 59 which is cooperable with the rib element 55 has hook arms 60 and 61 respectively which are cooperable with the overhanging edges 57 and 58 of the rib element 55. Due to the angled relationship between the rib and groove elements 55 and 59 at the overhanging edges 57 and 58, the flexible container is opened more easily from the outside by forces applied to the grip flanges 18 and 19 than from the inside due to forces applied to the side walls 10 and 11. For instance, the hook portion 62 of the hook arm 61 will more readily disengage with the angled edge 58 than the hook portion 64 will disengage with the angled edge 57.

The force differential achieved through the angled engaging surfaces of FIGURE 4 can be enhanced by providing a substantially heavier and more rigid hook arm at the interior side of the rib element as is indicated by the dotted line about the hook arm 60. Also, the spacing between the end face 65 of the hook arm 61 and the base portion 56 of the rib element 55 can be altered in order to increase or decrease the difference in forces required for opening the container from the outside and from the inside.

It will be understood that various modifications and combinations of the features disclosed herein may be accomplished by those versed in the art, and I desire to claim all such modifications and combinations as properly come within the scope and spirit of my contribution to the art.

I claim as my invention:

1. A flexible container in the form of a pouch having side walls forming an opening leading to the interior of the pouch and having interlocking rib and groove elements formed at the interior of the side walls for closing the container by pressing the elements together and for opening the container by drawing the elements apart,

said rib element having a base portion secured to one of the side walls and having a head portion secured to the base portion and spaced from said one side wall and having overhanging engaging edges, each of said engaging edges being parallel to said one side wall from the base to the extremity thereof and said engaging edges extending at opposite sides of the base portion for being engaged by hook arms of said groove clement,

said groove element having first and second hook arms forming a groove for receiving the rib element and having grip means for interlocking with said engaging edges of the rib element,

said first hook arm dis osed inwardly of the container relative to the rib element and being formed to be heavier and more rigid in the region between said one side wall of the container and the associated overhanging edge of the rib element than said second hook arm, said second hook arm being disposed outwardly of the container relative to the rib element.

2. A flexible container in accordance with claim 1 wherein said engaging edges of the rib element extend from opposite sides of said base portion and are spaced from said one wall of the container and wherein said first and second hook arms extend between said one wall and said engaging edges at respective sides of the rib element and wherein said first hook arm occupies substantially most of the space between said associated engaging edge and said one wall and said second book arm occupies substantially less than the space occupied by said first hook arm.

3. A flexible container in accordance with claim 1 wherein the heavier more rigid first hook arm is extended inwardly toward said base portion from the inside of the container by a greater distance than said second hook arm is extended toward said base portion from the outside of the container whereby said container opens more easily from the outside than from the inside.

4. A flexible container in the form of a pouch having side walls forming an opening leading to the interior of the pouch and having interlocking rib and groove elements formed at the interior of the side walls for closing the container by pressing the elements together and for opening the container by drawing the elements apart,

said rib element having a base portion secured to one of the side walls and having a head portion secured to the base portion and spaced from said one side wall and having overhanging engaging edges extending at opposite sides of the base portion for being engaged by hook arms of said groove element,

one of said engaging edges disposed inwardly of the container and forming an angle of less than 90 with the profile axis of said base portion and the other of said engaging edges disposed outwardly of the container and forming an angle of more than 90 with the profile axis of said base portion,

said groove element having first and second hook arms forming a groove for receiving the rib element and having grip means for interlocking with said engaging edges of the rib element,

whereby said container opens more easily from the outside than from the inside.

5. A flexible container in accordance with claim 4 wherein said hook arms have an angled portion formed complementarily with said angled engaging edges of said rib element.

6. A flexible container in accordance with claim 4 wherein one of said hook arms extends further inwardly toward said base portion from the inside of the container than the other of said hook arms extends inwardly toward said base portion from the outside of the container, whereby the container opens more easily from the outside than from the inside.

7. A flexible container in accordance with claim 4 wherein one of said hook arms disposed inwardly of the container is formed of flexible material which is heavier and substantially more rigid than the other hook arm disposed outwardly of the container.

8. A flexible container in the form of a pouch having side walls forming an opening leading to the interior of the pouch and having interlocking rib and grove elements formed at the interior of the side walls for closing the container by pressing the elements together and for opening the container by drawing the elements apart,

said r-ib element having a base portion secured to one of the side walls and having a head portion secured to the base portion and spaced from said one side wall and having overhanging engaging edges extending at opposite sides of the base portion for being engaged by hook arms of said groove element,

a first of said engaging edges extending inwardly of the container and the second of said engaging edges extending outwardly of the container,

said first engaging edge being spaced from said one side wall by a distance less than the corresponding spacing of the second engaging edge,

said groove element having first and second hook arms forming a groove for receiving the rib element and having grip means for interlocking with said engaging edges of the rib element,

said first hook arm disposed inwardly of the container and being longer than said second hook arm,

said first hook arm being substantially heavier and more rigid than said second hook arm and said first hook arm occupying substantially more of the space between said first engaging edge and said one side wall than the second hook arm similarly occupies between said second engaging edge and said one side wall.

References Cited UNITED STATES PATENTS DONALD F. NORTON, Primary Examiner.

US. Cl. X.R. 24-201 

